10.3.1 Use nature temperature over inland water

This is activated by setting LWATERTG2=.TRUE. If enabled points defined by having both fractions of nature temperature and inland water temperature, the inland water temperature is replaced by the nature temperature in level 2 (deep soil for ISBA Force-restore)

A typical usage of LWATERTG2=.TRUE. is to combine it with LEXTRAP_WATER=.TRUE. to force the inland water temperatures to be replaced by the nearest values of points where nature and inland water are both defined.